noun
working animal; draft animal
Refers to animals used for labor, such as pulling carts, plowing, or carrying loads. Both draft and pack animals are also used.
昔は牛や馬が主な使役動物だった。
In the past, cattle and horses were the main working animals.
使役動物の福祉も考える必要がある。
We also need to consider the welfare of working animals.
Compound of 使役 (しえき, 'work, labor') and 動物 (どうぶつ, 'animal'). The term is a straightforward modern coinage.